CBSE Class 3 Science – 9. Solid, Liquid, Gas (Notes)

     

 

Matter: Any substance that has mass, volume and occupies space is called matter.

 

Volume- The amount of space occupied by something is called volume.

 

Mass- The amount of matter contained in an object is called its mass.

 

Properties of Matter:

Life appearance

Hardness or softness

Solubility

 Density

Transparency

Conductivity etc.

 

States of Matter: There are three basic states of matter:

Solid

Liquid

Gas

 

 Solid: Those substances which have definite shape and volume are called solid.

 Ex. wood, bricks, plastic, stones, iron etc.

            

Properties of solid:

It has definite shape & volume.

It occupies space and has weight.

Most solids are hard.

 It don not flow on their own

 

Liquid: Those substances which have definite volume but indefinite shape are called liquid.

Ex. Water, milk, oil, juice etc.

Properties of liquid:

It does not have a shape of their own.

But it takes the shape of their container.

It too occupies space and has weight.

It can flow easily

 

Gas: Those substances which have indefinite volume & shape are called gas.

Ex. Oxygen, nitrogen, carbon dioxide etc.       

Properties of gas:

It does not have a shape of their own.

But it take the shape of their container

It occupies space and has weight.

It cannot be seen but can be feel or smell.

It flows in all direction easily

 

Classification of matter:

PHYSICAL STATE	SHAPE	VOLUME	FORCES OF ATTRACTION	SPACE BETWEEN THE PARTICLES
Solid	Fixed	Definite	Very strong	Close together
Liquid	Not fixed	Definite	Intermediate between solids and liquids	Intermediate between solids   and liquids
Gas	Not fixed	Indefinite	Very weak	Far apart

 

 

Change of form:

Evaporation        Changing of a liquid into gas is called evaporation.

Condensation      Changing of a gas into liquid is called condensation.

Freezing               Changing of a liquid into a solid is called freezing.

Melting                Changing of a solid into a liquid is called melting.